In recent years, hybrid and electric vehicles, which are provided with a battery, have been proposed, and some of them have been put into practice, to effectively use energy, in particular, regenerative energy as environmental measures. Typically, secondary batteries, which have been put to into practice and installed in vehicles so far, include, for example, lead storage batteries, nickel metal hydride batteries, or high powered lithium ion batteries. Some electric vehicles, such as electric cars, charge their batteries by plugging in the electric vehicle at a charging station. Other electric vehicles such as electric trains and light rail cars, are permanently connected to a power source through hardware in the railing or through overhead lines.
Recent trends in integrated transportation systems for electric vehicles, such as bus systems or other public transportation systems, have moved away from the use of permanent electrical connections to electric vehicle, as these systems are an eyesore, are unpopular, are costly to install and maintain, and can be unsafe. Some of these systems do not enable an electrical vehicle to run independent of a railing or overhead line. The speed of charging can be very pertinent for a heavy-duty vehicle, such as a bus, that may be regularly recharged within small time frames. More recent integrated transport systems may use fixed charging stations to rapidly charge heavy duty batteries used in electric vehicles. In one example, an electric vehicle may need to complete a charge in less than ten minutes that is sufficient to enable it to complete its normal route of nine to twelve miles in an hour before having to recharge. Charging an electric vehicle in less than ten minutes, particularly for large, heavy-duty vehicles such as buses, vans, or large trucks, is generally only considered possible with certain types of battery chemistries such as lithium titanate or ultra-capacitors that are capable of a sustained high charge rate or C-rate. However, ultra-capacitors do not contain sufficient energy density to provide the necessary range to complete a given route of this length without recharging. Also, the rapid charge and discharge of batteries capable of high C-rates on a repeated basis may lead to increased wear and decreased life for the batteries, which increases the cost of operation for owners.
Thus, a need exists for energy storage systems and associated methods that can be rapidly charged and provide equivalent performance to existing high C-rate energy storage systems capable of high C-rates while using a different energy storage configuration.